SSL/TLS Certificate Lookup

Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted

SSL/TLS Certificate for f-tekno.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
f-tekno.jp
Valid from
Jul 31, 2026
Valid until
Oct 29, 2026 (49 days remaining)
Public key
RSA 2048-bit
Serial
06DF760EF07A8028000F3BA155D56A9B6459
SHA-256 fingerprint
EF:1B:B0:03:41:0B:F1:E3:2D:51:68:E5:D4:3A:E9:EC:A5:C7:1D:F8:98:5D:D3:4C:74:3A:F0:E9:0B:BB:F5:EA
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
*.f-tekno.jp, f-tekno.jp

Certificate Authority Authorization (CAA)

No CAA policy is published for this domain — any certificate authority may issue for it.

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Uptime

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DNS changes

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TLS certificate

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